I know the __( _____ )_ (serious) of the matter. Today our rivers and lakes are _( _____ )_____ (serious) polluted, and so our land and air.
出自:四川民族学院大学英语复习题二

完成拼图验证

按住下方滑块,将拼图拖到缺口处后松开。

拼图背景,将小拼图拖到缺口处
向右拖动滑块